Light-Emitting Device Package for Back Light and Manufacturing Method Thereof

This is a continuation of U.S. application Ser. No. 17/721,052, filed Apr. 14, 2022, which claims the priority benefit under 35 U.S.C. § 119 to Korean Patent Application No. 10-2021-0052388, filed Apr. 22, 2021, in the Korean Intellectual Property Office, the disclosures of which are incorporated herein in their entirety by reference.

Embodiments of the present disclosure relate to a light-emitting device package for back light and a manufacturing method thereof, and more particularly, to a light-emitting device package for back light that may be used for display or lighting purposes and a manufacturing method thereof.

A light-emitting diode (LED) refers to a type of semiconductor device capable of realizing light of various colors by forming a light-emitting source by forming a PN diode of a compound semiconductor. Such a light-emitting device has a long lifespan, may be miniaturized and lightweight, and may be driven at a low voltage. In addition, these LEDs are strong against shock and vibration, do not require warm-up time and complicated driving, and may be packaged after being mounted on a substrate or lead frame in various forms, so they may be modularized for various purposes and applied to a back light unit or various lighting devices, etc.

In general, a method of manufacturing a light-emitting device package for packaging a light-emitting device consists of a process of mounting the light-emitting device on the lead frame, forming a reflective member, and then forming a light conversion member above the light-emitting device.

However, in the case of these conventional light-emitting device packages, size or thickness is relatively large, so products may not be miniaturized or ultra-thin.

In order to solve this problem, a chip scale package (CSP) process of mounting a plurality of light-emitting devices, forming an optical member at once, and then individualizing the package to enable miniaturization and ultra-thinness of the package is used.

On the other hand, in conventional light-emitting device packages applied to edge-type backlight units, which are an isotropic light-emitting type, color shading may occur between the light-emitting device packages because a directivity angle is narrow. In addition, in order to solve such color shading, when intervals of light-emitting device packages are reduced by increasing the number of light-emitting device packages as before, cost is increased.

An object of the embodiments of the present disclosure for solving the above problems is to provide a light-emitting device package for back light capable of increasing a directivity angle and increasing light efficiency by exposing a side surface of a wavelength conversion member, and a manufacturing method thereof.

Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.

An embodiment of the present disclosure provides a light-emitting device package includes an LED chip including a substrate having an upper surface, a semiconductor laminate structure formed under the substrate, and a first conductive connection pad and a second conductive connection pad formed under the semiconductor laminate structure, a wavelength conversion member having one surface in contact with the upper surface of the substrate, a light transmitting member covering a side surface of the LED chip and one surface of the wavelength conversion member adjacent to the side surface, and a reflector including at least one first region covering a side surface of the wavelength conversion member and the light transmitting member, and at least one second region covering the light transmitting member and exposing the side surface of the wavelength conversion member.

In one embodiment of the present disclosure, the second region of the reflector may be formed at positions corresponding to two side surfaces facing each other among the four side surfaces of the wavelength conversion member.

In one embodiment of the present disclosure, the second region of the reflector may be formed at positions corresponding to three side surfaces of the four side surfaces of the wavelength conversion member.

In one embodiment of the present disclosure, one surface of the light transmitting member connecting the side surface of the LED chip and the one surface of the wavelength conversion member may be formed in a curved surface.

In one embodiment of the present disclosure, the one surface of the light transmitting member may be concave toward the LED chip and the wavelength conversion member.

In one embodiment of the present disclosure, a width of the wavelength conversion member may be greater than a width of the LED chip.

In one embodiment of the present disclosure, a width of the reflector corresponding to the second region may be the same as a width of a portion of the wavelength conversion member which protrudes from the LED chip.

In one embodiment of the present disclosure, a width of the reflector corresponding to the first region may be greater than a width of a portion of the wavelength conversion member which protrudes from the LED chip.

Another embodiment of the present disclosure provides a light-emitting device package including an LED chip including a semiconductor laminate structure, a substrate formed above of the semiconductor laminate structure, and a first conductive connection pad and a second conductive connection pad formed under the semiconductor laminate structure, a wavelength conversion member disposed above the substrate, a light transmitting member covering at least one side surface of the LED chip, and a reflector formed on a side surface of the light transmitting member, wherein the reflector is disposed to surround the side surface of the LED chip and side surfaces of the wavelength conversion member and the light transmitting member, and exposes at least one side surface of the wavelength conversion member.

In one embodiment of the present disclosure, one surface of the light transmitting member connecting the at least one side surface of the LED chip and one surface of the wavelength conversion member may be formed as a curved surface.

In one embodiment of the present disclosure, the one surface of the light transmitting member may be concave toward the LED chip and the wavelength conversion member.

In one embodiment of the present disclosure, the light transmitting member may be arranged to cover all side surfaces of the LED chip and one surface of the wavelength conversion member adjacent to the side surface.

In one embodiment of the present disclosure, a width of the wavelength conversion member may be greater than a width of the LED chip.

In one embodiment of the present disclosure, a width of the reflector corresponding to the exposed side surface of the wavelength conversion member may be the same as a width of a portion of the wavelength conversion member which protrudes from the LED chip.

An embodiment of the present disclosure provides a method of manufacturing a light-emitting device package including preparing a plurality of LED chips including a substrate having an upper surface, a semiconductor laminate structure formed under the substrate, and a first conductive connection pad and a second conductive connection pad formed under the semiconductor laminate structure, arranging upper surfaces of the plurality of LED chips on a wavelength conversion sheet, forming a light transmitting member between a side surface of the LED chip and one surface of the wavelength conversion member adjacent to the side surface, cutting the wavelength conversion sheet between the plurality of LED chips to form a plurality of wavelength conversion members arranged at predetermined intervals, and forming a reflector including a first region covering a side surface of the wavelength conversion member and the light transmitting member and a second region covering the light transmitting member and exposing a side surface of the wavelength conversion member.

In one embodiment of the present disclosure, forming the reflector may include filling a reflective material between the plurality of LED chips and the plurality of wavelength conversion members, cutting the wavelength conversion member and the reflector to form the first region, and cutting the reflector to form the second region.

In one embodiment of the present disclosure, a width of the wavelength conversion member may be greater than a width of the LED chip.

In one embodiment of the present disclosure, a width of the reflector corresponding to the second region may be the same as a width of a portion of the wavelength conversion member which protrudes from the LED chip.

In one embodiment of the present disclosure, the wavelength conversion sheet may be formed on a temporary support sheet, and the temporary support sheet may be removed after forming the reflector.

In one embodiment of the present disclosure, one surface of the light transmitting member connecting the side surface of the LED chip and the one surface of the wavelength conversion member may be formed in a curved surface.

Other aspects, features and advantages other than those described above will become apparent from the following detailed description of the drawings, claims and disclosure.

Hereinafter, the following embodiments will be described in detail with reference to the accompanying drawings, and when described with reference to the drawings, the same or corresponding components are given the same reference numerals, and the overlapping description thereof will be omitted.

Since the present embodiments can apply various transformations, specific embodiments are illustrated in the drawings and described in detail in the detailed description. Effects and features of the present embodiments, and a method of achieving them will become clear with reference to the details described later in conjunction with the drawings. However, the present embodiments are not limited to the embodiments disclosed below and may be implemented in various forms.

In the following embodiments, terms such as first, second, etc. are used for the purpose of distinguishing one component from other components without limiting meaning.

In the following examples, the singular expression includes the plural expression unless the context clearly dictates otherwise.

In the following embodiments, terms such as include or have means that the features or components described in the specification are present, and the possibility that one or more other features or components will be added is not excluded in advance.

In the following embodiments, when it is said that a part such as a unit, region, or component is on or on another part, it is not only when it is directly on the other part, but also another unit, region, component, etc. is interposed therebetween. cases are included.

In the following embodiments, terms such as connect or couple do not necessarily mean direct and/or fixed connection or coupling of two members unless the context clearly indicates otherwise, and does not exclude that another member is interposed between the two members.

It means that a feature or element described in the specification is present, and does not preclude the possibility that one or more other features or elements may be added.

In the drawings, the size of the components may be exaggerated or reduced for convenience of description. For example, since the size and thickness of each component shown in the drawings are arbitrarily indicated for convenience of description, the following embodiment is not necessarily limited to the illustrated bar.

1 FIG. 2 FIG. 1 FIG. 3 FIG. 1 FIG. is a diagram schematically illustrating a light-emitting device package according to an embodiment of the present disclosure,is a cross-sectional view taken along line II-II′ of, andis a cross-sectional view taken along line III-III′ of.

1 3 FIGS.to 10 100 110 120 130 Referring to, a light-emitting device packagemay include an LED chip, a wavelength conversion member, a light transmitting memberand a reflector.

100 101 102 103 104 The LED chipmay include a substrate, a semiconductor laminate structure, a first conductive connection padand a second conductive connection pad.

101 The substratemay be a sapphire substrate including a light-emitting surface.

102 101 102 103 104 The semiconductor laminate structuremay be a gallium nitride-based semiconductor laminate structure formed on the substrate. The semiconductor laminate structureincludes a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer. At this time, although illustrated briefly in the drawings, a part of the second conductive semiconductor layer and the active layer are selectively removed, so that a part of the first conductive semiconductor layer is exposed, and the first conductive connection padmay be connected through the exposed area. In addition, the second conductive connection padis connected to the second conductive semiconductor layer.

110 100 101 110 110 The wavelength conversion membermay be disposed above the LED chip, specifically, above the substrate. The wavelength conversion membermay be formed of a fluorescent sheet including a fluorescent substance. However, the present disclosure is not limited thereto, and the wavelength conversion membermay be formed by a mixture of one or more fluorescent substances and an encapsulant made of, for example, a resin powder on a temporary support sheet to be described later.

100 110 The LED chipis preferably a blue LED chip, and the wavelength conversion membermay include a red fluorescent substance that emits red light when excited by blue light and a green fluorescent substance that emits green light, or may include a yellow fluorescent substance that emits yellow light when excited by blue light.

110 101 110 1 100 110 100 100 The wavelength conversion membermay cover an upper surface of the substrate. In this case, a width of the wavelength conversion membermay be greater than a width wof the LED chip. That is, one surface of the wavelength conversion membermay have a larger area than the LED chipand may cover the upper surface of the LED chip.

120 1 3 100 1 3 110 1 3 120 120 120 1 3 100 1 3 110 1 3 2 4 100 2 4 110 2 4 The light transmitting membermay cover at least one side surface Aand Aof the LED chipand one surface Band Bof the wavelength conversion memberadjacent to the side surface Aand A. The light transmitting membermay be made of a silicon material having transparency. The light transmitting membermay be formed to correspond to a portion to be exposed. As an embodiment, the light transmitting membercovers only one side surface Aand Aof the LED chipand one surface Band Bof the wavelength conversion memberadjacent to one side surface Aand A, may not be formed on the other side surface Aand Aof the LED chipwhich is not exposed and the other surface Band Bof the wavelength conversion memberadjacent to the other side surface Aand A.

120 1 2 3 4 100 1 2 3 4 110 1 2 3 4 120 1 2 3 4 100 As another embodiment, the light transmitting membermay be disposed to cover all side surfaces A, A, Aand Aof the LED chipand one surface B, B, Band Bof the wavelength conversion memberadjacent to the side surfaces A, A, Aand A. Hereinafter, for convenience of description, a case in which the light transmitting memberis disposed on all side surfaces A, A, Aand Aof the LED chipwill be mainly described.

1 120 1 2 3 4 100 1 2 3 4 110 1 120 100 110 One surface Sof the light transmitting memberthat connects the side surfaces A, A, Aand Aof the LED chipand the one surface B, B, Band Bof the wavelength conversion membermay be formed as a curved surface. The one surface Sof the light transmitting membermay be concave toward the LED chipand the wavelength conversion member.

120 1 2 3 4 100 110 The light transmitting membermay transmit light emitted from the side surfaces A, A, Aand Aof the LED chipto the wavelength conversion member.

130 100 110 120 110 The reflectoris arranged to surround the side surface of the LED chip, the side surface of the wavelength conversion member, and the light transmitting member, but may expose at least one side surface of the wavelength conversion member.

130 100 130 100 130 The reflectormay be made of a reflective material that reflects the light emitted from the LED chip. In another embodiment, the reflectormay be made of an absorbing material that absorbs the light emitted from the LED chip. Hereinafter, for convenience of description, a case in which the reflectoris made of the reflective material will be mainly described.

130 130 A base material of the reflectormay be an organic or inorganic resin material. For example, the reflectormay contain the organic or inorganic resin material such as silicone, epoxy, heat-resistant resin polyimide, phenol resin, melamine resin, unsaturated polyester resin, tritans, and the like.

130 120 The reflective material may be a material that reflects light using titanium dioxide (TiO2), barium sulfate (BaSO4), and the like. In addition, the reflectormay further include boron nitride (BN), aluminum nitride (AlN), aluminum (Al), graphite, and the like. Through this, the light transmitting membermay improve heat dissipation performance.

130 110 120 120 110 130 110 The reflectormay include a first region covering the side surface of the wavelength conversion memberand the light transmitting memberand a second region covering the light transmitting memberand exposing the side surface of the wavelength conversion member. In other words, the first region may become a non-luminous region because the side surface of the wavelength conversion memberis covered with the reflector, and the second region may become a luminous region because the side surface of the wavelength conversion memberis exposed.

3 130 2 110 100 4 130 2 110 100 In this case, a width wof the reflectorcorresponding to the second region may be the same as a width wof a portion in which the wavelength conversion memberprotrudes from the LED chip. Alternatively, a width wof the reflectorcorresponding to the first region may be greater than the width wof the portion where the wavelength conversion memberprotrudes from the LED chip.

130 130 104 100 1 130 2 103 104 100 Meanwhile, the reflectormay be formed to cover the side surfaces of the first conductive connection padand the second conductive connection padof the LED chip. In other words, a bottom surface Lof the reflectormay be disposed on the same plane as bottom surfaces Lof the first conductive connection padand the second conductive connection padof the LED chip.

4 5 FIGS.and 10 10 are diagrams schematically illustrating various embodiments of a light-emitting device package′ and″ according to an embodiment of the present disclosure.

10 10 10 110 130 100 The light-emitting device package,′ and″ according to one embodiment of the present disclosure exposes the side surface of the wavelength conversion memberthrough the structure of the reflector, so that the other surface than the upper surface of the LED chipmay be extended to a light-emitting surface.

1 FIG. 130 10 As an embodiment, as illustrated in, the second region of the reflectoris formed at positions corresponding to two side surfaces facing each other among the four side surfaces of the wavelength conversion member, so that the light-emitting device packagemay be emitted from three surfaces through the upper surface and the two side surfaces.

4 FIG. 130 10 As another embodiment, as illustrated in, the second region of the reflectoris formed at positions corresponding to three side surfaces among the four side surfaces of the wavelength conversion member, so that the light-emitting device package′ may be emitted from four surfaces through the upper surface and the three side surfaces.

5 FIG. 130 10 As another embodiment, as illustrated in, the second region of the reflectoris formed at positions corresponding to all four side surfaces of the wavelength conversion member, so that the light-emitting device package″ may be emitted from five surfaces through the upper surface and the four side surfaces.

130 10 In addition, although not illustrated, the second region of the reflectoris formed at a position corresponding to one side surface among the four side surfaces of the wavelength conversion member, so that the light-emitting device packagemay be emitted from two surfaces through the upper surface and the one side surface.

The light-emitting device package according to the embodiments of the present disclosure having the above structure exposes the side surface of the wavelength conversion member, so that the directivity angle may be expanded to the exposed area, the amount of light may be increased, and various directivity characteristics may be provided by selecting the exposed surface as necessary.

6 11 FIGS.to are views for explaining a method of manufacturing a light-emitting device package according to an embodiment of the present disclosure.

6 FIG. 100 Referring to, in a method of manufacturing the light-emitting device package according to one embodiment of the present disclosure, first, a plurality of LED chipsincluding the substrate including the upper surface, the semiconductor laminate structure formed under the substrate, and the first conductive connection pad and the second conductive connection pad formed under the semiconductor laminate structure are prepared.

100 110 100 110 In this case, the upper surface of the plurality of LED chipsmay be arranged to contact a wavelength conversion sheet′. The plurality of LED chipsmay be arranged on the wavelength conversion sheet′ at regular intervals.

110 200 110 110 200 The wavelength conversion sheet′ may be formed on a temporary support sheet. The wavelength conversion sheet′ may be composed of the fluorescent sheet containing the fluorescent substance. Alternatively, the wavelength conversion membermay be formed by the mixture of one or more fluorescent substances and the encapsulant composed of, for example, resin powder on the temporary support sheet.

7 FIG. 120 100 110 120 100 110 Referring to, the light transmitting memberis formed between the side surface of the LED chipand the one surface of the wavelength conversion memberadjacent to the side surface. The light transmitting membermay be made of the silicon material having transparency, and may be formed between the LED chipand the wavelength conversion memberby an injection method.

120 110 110 The light transmitting membermay be formed only at a position corresponding to the side surface to be exposed among the side surfaces of the wavelength conversion member, and may be formed to surround all side surfaces of the wavelength conversion member.

8 FIG. 110 100 110 110 100 Referring to, the wavelength conversion sheet′ between the plurality of LED chipsmay be cut to form the plurality of wavelength conversion membersarranged at a predetermined interval. The wavelength conversion membermay have the width greater than the width of the LED chip.

9 FIG. 9 FIG. 100 110 130 100 Referring to, the reflective material may be filled between the plurality of LED chipsand the plurality of wavelength conversion members. As illustrated in, the reflective materialis filled between the plurality of LED chips, and may be filled up to the side surfaces of the first conductive connection pad and the second conductive connection pad.

10 10 FIGS.A andB 10 FIG.A 2 FIG. 110 110 110 130 110 3 130 2 110 100 Referring to, the plurality of wavelength conversion membersmay be cut to form the first region and the second region.is a view for explaining the formation of the second region, and the second region may be formed by removing all of the reflective material between the wavelength conversion members. In other words, since the reflective material is all removed for the intervals of the plurality of wavelength conversion members, the reflectormay expose the side surface of the wavelength conversion memberthereafter. The width wof the reflectorcorresponding to the second region may be the same as the width wof the portion in which the wavelength conversion memberprotrudes from the LED chip(see).

10 FIG.B 110 110 is a view for explaining the formation of the first region, the first region may be formed by cutting between wavelength conversion members. Unlike the second region, in the first region, not all of the reflective material is removed, but the reflective material covering the side surface of the wavelength conversion membermay be left by being cut only at a predetermined interval.

110 120 Through this method of manufacturing the light-emitting device package, the reflector including the first region covering the side surface of the wavelength conversion memberand the light transmitting memberand the second region covering the light transmitting member and exposing the side surface of the wavelength conversion member may be formed.

11 FIG. 200 Thereafter, as illustrated in, the temporary support sheetis removed, so that the plurality of LED chips may be individually separated.

As described above, the method of manufacturing the light-emitting device package according to an embodiment of the present disclosure may manufacture a multi-faceted light-emitting device while simplifying a manufacturing process and reducing costs.

The light-emitting device package according to the embodiments of the present disclosure exposes the side surface of the wavelength conversion member, so that the directivity angle may be expanded to the exposed area, the amount of light may be increased, and various directivity characteristics may be provided by selecting the exposed surface as necessary.

The method of manufacturing the light-emitting device package according to embodiments of the present disclosure may manufacture the multi-faceted light-emitting device while simplifying a manufacturing process and reducing costs.

As such, the present disclosure has been described with reference to one embodiment shown in the drawings, but this is merely exemplary, and those of ordinary skill in the art will understand that various modifications and variations of the embodiments are possible therefrom. Accordingly, the true technical protection scope of the present disclosure should be determined by the technical spirit of the appended claims.